There are numerous different types and forms of operating stages being used by Surgeons to aid in positioning and holding devices such as retractors during operations. They generally take the form of a rigid ring from which various retractors may be mounted using a variety of different connecting devices. These stages are usually mounted on a suitable arm that positions the ring in fixed relation to the operating table or the like on which the patient is positioned.
Retractors are normally mounted on the operating stage or ring by some form of hooking or fixed clamping type mechanism such as a screw clamp that locks the retractor in a fixed position relative to the ring. These clamping devices generally require two hands to operate, one to place the retractor in position in the clamp and the other to screw the clamping mechanism to firmly clamp the retractor in fixed position. Obviously, these systems are inconvenient to use and provide no release to permit relative movement of the retractor and operating stage in the event of an unforeseen relatively high forces that may cause damage to the patient is applied to the retractors.
Also, during many operations, some means must be provided to anchor sutures which are used, in the manner of retractors, for example, to hold back the skin or parts of the body around the operative site. These sutures are generally tied off or weighted off by pinning them to the drapes or by attaching weights or the like; in some cases they are clamped or otherwise connected to the stage.
U.S. Pat. Nos. 4,430,991 and 4,434,791 issued Feb. 14, 1994 and Mar. 6, 1994 respectively, both to Danelle, both show notches on the outside of an operating stage or ring and utilize the notches to receive collapsible tubes and wedge the tubes into position to hold the tubes. One of the ends of each tube is connected to a retractor hook or the like and the wedging action clamps the tube to position the retractors relative to the operating stage.
When sutures are used the sutures pass over the top of the stage or ring before they are clamped into position and thus, tend to limit mobility of the retractors circumferentially around the ring.